Coal loading machine



March 5, 1957 J. B. MQDADE com. LOADING MACHINE 8 Sheets-Sheet l Filed Oct. l0, 1951 March 5, 1957 J. B. MCDADE 2,783,902

COAL LOADING MACHINE Filed Oct. l0, 1951 8 Sheets-Sheet 2 l INVENTOR ATTORNEY March 5, 1957 J. B. MCDADE 2,783,902

COAL LOADING MACHINE Filed Oct. l0, 1951 8 Sheets-Sheet 3 ATTORNEY J. B. MCDADE COAL LOADING MACHINE Marh 5, 1957 8 Sheets-Sheet 4 Filed IOC.. 10, 1951 .r All, .1 I lllvxx H IN VENTOR BY /FWQORNEY March 5, J, B, COAL LOADING MACHINE:

8 Sheets-Sheet 5 Filed Oct. l0, 1951 JM/M/I BY ATTORNEY March 5, 1957 J. B. MCDADE 2,783,902

COAL LOADING MACHINE Filed Oct. l0, 1951 8 Sheets-Sheet 6 XXX:

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.n BY ATTORNEY March 5, 1957 Filed Oct. lO. 1951 J. B. MQDADE COAL LOADING MACHINE 8 Sheets-Sheet 7 IN VENTOR MM5/Kfm@ March 5, 1957 J. B. MoDADE COAL LOADING MACHINE 8 Sheets-Sheet 8 Filed Oct. 10, 1951 INVENTOR Jmm/e 'ATTORNEY United States Patent CUAL LOADINGVMCHIE John B. McDade, ScrantomPa. Application October 10, 1951, Serial No. *250K-N59A 15 Claims. (Cl. 214-137) This invention relates to coal loading machines of the character used for loading coal from narrow veins,4- and more particularly to a coal loading machine havingwa novel rotatable shovel provided with separate hydraulic mechanisms for effecting reciprocation' and rotation 'of the shovel in connection with the loading and unloading operations. Additionally, the invention relates to improved power plants for self-contained coal loadingmmachines incorporating holding jacks on aV skidror a Caterpillar-supported turntable, and the shovel and itsjactuating mechanism are tilt'ably supported on the turntable and rotatable therewith.

In my prior Patents 2,441,581 and 2,441,582', pf'May 18, 1948, I have disclosed and'claimed coal: loadingmja# chines of the vertically tiltable -type having `holdingrjacks, and unitary hydraulic mechanisms `for reciprocating. and rotating lthe shovels, together withlspeeial operating` mechanisms for the selective control of the shovel vreciprocating and rotating devices. l

I have now found that a much more `simple, compact, eicient, exible and powerful coal loader can be obtained by providing a unitary motor Vdrive for the power system comprising separate hydraulic power units `forthe shovel reciprocating and rotating mechanisms, as well asfproviding a novel, axially-supported shovel of improved design and increased capacity, and of improved'maneuverability in both load'ed'and unloaded condition. j Because ofthe improveddistribution ofthe power- 7loads andfthe reductionin size ofthe velements of the power equipment, the latter can be maintained at minimum size anddistributed on a turntable to best advantage, whereby the capacity', 'efficiency and maneuverabili'ty of the coal loading machine is greatly increased, while, as noted, the overall size limitations are appreciably reduced. Addie tionall'y, the novel coalloader issusceptible of remote control operation from outside of narrow seams or workings, with consequentimprovement in working conditions for the machine operator. It 'is',the'refore, among Vthe objects ofthe present invention to provide an improved coal loadingtmachine, which is movable under its own power, and which is Ycharacterized by increased load' capacity and iiexibilityY of operation.

It is also among the objects of the invention to provide a coal loading machine'having dual power units in a single assembly an'd driven by a single motor, the whole being mounted on a skid or Caterpillarisupported turntable, together with' tiltable power shovel operatingmechf anisms, the'shovel'ope'rating"mechanisms being self-balancing or equipoisedin 'retracted position, and the shovel being self-supporting in extended position, whereby no unbalanced loads are imposed on thetiltingmechanisms.

The invention also comprehends as features ofnovelty, an electric motor-driven, dual hydraulic power units and solenoid controls-therefor, together with tlexiblepowerI cablesandmachine-mounted, or remote control equipe ment.

2,783,962 -APatented Mar. 5, 1957 A'Other and more detailed objects of the invention include a reciprocable top rod assembly for rotating the shovel, including a traveling manifold flexibly coupled to a separate hydraulic power unit; a power ram reciprocable in a fixed cylinder rigid with a `fulcrumed bearing guide and serving as a bearing for the traveling manifold; a shovel rotatably mounted at the end of the power ram; means inthe top rod assembly cooperating with the power ram and shovelI and effective to insure a predetermined forward travelv of the shovel into the base of a pile of ,coal before rotation of the shovel on its axis is effected, whereby the .pay load picked up by the shovel is practically doubled; the provision of a pivoted wheel support for the sh'oveL-whereby the weight of the shovel and its contents is supported by the wheel in all forward positions of the po'werra'm and associated guide rods, and' no lever arm effect is imposed on the piston and guide rods; the provision ofV opposed, self-wedging grab jacks associated with the power piston crosshead and hydraulically coupled withlth'e hold jack for selective operation; the provision of a' tilt locking mechanism for the tiltable fulcrum guide and operable upon retraction of the ram, top rod piston and back support to fully retracted position, whereby the loaded shovel is counterbalanced and the turntable is mov- 'able to'traiislate the shovel to any desired unloading position; and the provision of interlockingl solenoid controls for the hydraulic units, whereby positive sequential operationrofthe equipment is assured.

'The above and other desirable objects ofthe present invention 'will be' more clearly understood by reference to" the accompanying drawings, in which is illustrated a nove coal loading 'machine incorporating preferred embodiments of the invention, by way of example only, as other specific installations may incorporate the novel features herein without departing from the spirit and scope ofthe present invention.

yln the drawings, like numerals refer to throughout the several views, in which Figure 1 is a schematic top plan view of the machine assembly with the shovel or scoop in completely retracted position, certain of the structures being shown in broken section, and the hydraulic lines and controls connected with thepower units; 4 Fig;V 2 is 'a plan view of the turntable showing the mounting vof the power units and control equipment the ram and shovel actuating equipment being shown in broken section;

Fig;` 3 isa' vertical section through-the hold ljack and mounting skid with the teeter block shown inelevation and associated equipment in section; Y

Fig; 4`is a side view partly in broken section of the assembly shown in Figs. l and 2, with portions-of thc hydraulic actuating mechanisms -broken awayr'and with the top rod inretracted position, showing the Ylip -of the shovel at the beginning of the loading stroke; certain of the power elements beingomitted to show the back barpower cylinder mounting;

similar parts Fig. 5`is a schematic view illustrating the travel of the` Fig. 1l is a longitudinal section taken on line 11-11 of Fig. 10, showing the details of the grab jack mechanism, with the fixed mounting of the top rod, and ram housing in the teeter block, and the securing of the telescoping manifold side rods and the ram in the bucket cross-head;

Fig. 12 is a fragmentary vertical section through the teeter block, showing the details of the ram housing, ram cylinder, and ram piston mounting therein, the teeter block support and portion of the top rod and its mounting being shown in elevation;

Fig. 13 is a section taken on line 13-13 of Fig. 11, showing the details of the bucket mounting, and

Figs. 14 and 15 are a plan and section View, respectively, of a modified hold-jack assembly.

The novel coal loader herein comprises a plurality of structural units and their component parts integrated into a unitary mechanism which is composed essentially of a loading head rotatively mounting a bucket or shovel, and dual, hydraulically controlled actuators, interconnected, both mechanically and hydraulically, and effective to reciprocate the loading head and rotate the shovel or scoop. Additionally, the loader assembly includes a traveling base and support for the assembly, mounting a xed pivot or standard in its center, the standard incorporating a hold jack; a turntable mounted for rotation on the standard; a hydraulic turn motor, a tilting fulcrurn standard, or trunnions, at the front of the turntable; a fulcrum guide or teeter block trunnioned in the standard, tiltably and reciprocably mounting the loader head actuators; and a motor-driven, dual hydraulic power unit mounted at one side of the turntable. The loader shovel, bucket, or scoop, extends across the entire front of the machine, and is movably supported on a cross-head having a pivoted caster so that there is no unbalanced or unsprung weight in any retracted or extended position of the loader head. The stability of the machine is considerably increased by lowering the centers of gravity of the component structural supporting and actuating units, which is accomplished by the design and use of relatively flat units, extending over a maximum of area, whereby the entire structure is relatively squat. By reason of this improved assembly, maximum stability is assured at all times. With the shovel using an axially suspended cylindroidal structure, its height and vertical operating head roorn can be reduced to a minimum without sacrificing the increased load carrying capacity of the machine.

Considering the assemblage more in detail, and for the purpose of setting up the specific orientation of the component units and their mutual cooperationy as a structural and mechanical entity, the novel machine, as shown in Figs. 1, 2, and 3, will be seen to comprise the following elements:

A. Skid base or support, mounting a vertical axis incorporating a hold jack;

B. Turntable rotatably mounted on the axis and including platform bases for units;

C. Dual, motor driven hydraulic unit on one side of the turntable;

D. Hydraulic turn motor and hydraulic tilting lock;

E. Teeter block for tiltably mounting the load gathering mechanism at the forward edge of the turntable and mounting the loading head actuators;

F. Loading head actuator;

G. Shovel rotator;

H. Shovel structure and supports, including grab jack and mounting therefor, and

I. Hydraulic connections and controls therefor.

Referring now to the drawings, the novel coal loader is seen to comprise a skid base, rotatably mounting a turntable, on which are mounted the fixed units comprising the fulcrum guide supports, tilting lock, hydraulic turn motor, hydraulic power units for the hydraulic actuators, and their common driving motor together with:v

arcanos r the necessary interlocking controls. Power is supplied to the motor by a power line from a control box, which is electrically connected, through slip rings on the vertical axis of the machine, with a main power cable having an entrant in the skid base.

The several units and their component elements will be separately described, after which the hydraulic connections will be detailed, followed by a specific description of the operation of the machine as an entity by the use of electric push button controls for the hydraulic power units and valved hydraulic connections to the hydraulic actuators.

Skid base, hydraulic jack, and turntable assembly and mounting Referring to the drawings, and more particularly to Figs. 2, 3 and 4, the mounting of the holding jack and the turntable on the skid base will be described.

The skid base comprises a Sledge 1, having a skid plate or bottom 2 provided with a central annular boss 3, having a flat top bearing surface 4 and a lateral entrant 5 for the power cable. The sledge is provided further with tapering side walls 6 and an annular rim or top 7, and a cable entrant 8 in alignment with the entrant 5 in the boss 3. The sledge may be of any suitable configuration, either circular or polygonal.

The hydraulic jack and the turntable, as shown in Figs. 2 and 3, are'keyed or locked in operative position in a manner now to be described: A central shaft 10 has a bottom section 11 fitted into the boss 3 and secured in place as by screws 12, tapped around the annular joint of the shaft with the boss 3. The shaft 10 is shouldered, as indictaed at 13, to provide bearing engagement against the annular bearing surface 4. Immediately above the shouldering 13 the shaft forms a bearing surface 14 terminating in a recessed screw-threaded portion 15. The shaft is then reduced in diameter and continued upwardly' as indicated at 16, the top portion being hollow, as indicated at 17, to provide a cylinder for the hydraulic jack. The base portion of the shaft is centrally apertured, as indicated at 18, and is provided with a lateral opening at the bottom in alignment with cable entrant 5. A diametric transverse opening 19 connects the top of aperture 18 with the surface 16 of the shaft, and a collector ring support, as will be described more in detail hereinafter.

The hydraulic jack, designated generally by the numeral 20, includes a piston 21, having an axial duct 22 extending its entire length, and closed at the top section 23 by any suitable means, such as a tap or machine screw 24. The bottom of the piston is shouldered, as indicated at 25, and the piston reciprocates in the chamber 17 of the shaft 10. The flanged end of the piston is provided with. a top limit stop, comprising washers 26, held in place by a lock ring 27. An oil entrant is tapped into the axialoil duct at an angle, desirably at 45, and is connected to a suitable iiexible conduit 28, as will be described more in detail hereinafter. The jack top, designated generally by the numeral 29, is secured to the top of the piston in any suitable manner, care being taken to insure the selfseating bearing engagement of the head under operative conditions.

As shown in Figs. 3 and 4, the turntable 30 is rotatably.

.supported on the shaft 10 in the following manner: Au

annular ball bearing race 31 is fitted over shaft 10 in drive fit engagement with bearing surface 14k of the shaft, so that its bottom surface 32 has aligned bearingl engagement on the top surface 4 of the supporting boss 3 of the sledge or skid base 1. The top surface 33 of the annulus 31 is engaged by lock nut 34, which is turned up on the screw-threaded section 15 of shaft 10 and clamps the annular bearing member tightly in place. A second, concentric annnlus 35 serves with the first annulus 31 as a race or cage for ball bearings 36. The

` turntable 30 is formed integral with anannular casting 37, serving as a hub for the turntable, and is secured meemaak thereto-:many desredrmannerai The hubitincorporates'- axentrallyfapertured itop.; 37; and :islzttedfonnandioven theaoutside ball;race .35; An 'annular .bearingtplaterS Y is'csecured-to the bottom' of members37i by@l machine screws; .on bolts139g. and :clamps the; bottom: surface tof balli..raceJrSSg-I as. shown; A2 greaseLfsealgSS/f iss` providedv betweerr, thee outer# surface;` of lock nut Q34 fand ther. edge ofsthefapertnre in the-top 37.-

Theeturntable is rotated ;about;theeshaftxam the:ol1 lowingmanner: Ahydraulic turn motor `40:(Fig`s.z 1` and 2);;haying;a shaft coupling: 41, is..connected .through gear box 42, to a depending pinion geart43: Thezpinionfgean meshes:withringzgearz.44 (Eig-.2), mountedinfrchannel 4$-formed iniihe upper surfacetofibbt'tom :platei 21ofwthe= skids-.baser- The ring gear; is .secured in'- placev by-i machine screws.46;f1orrtheelike:. Thefhydraulic turn-.motori and other lauxiliary equipment:iiXedlyr-secured to: the` turntabler-foi 'rotatio1r,therewith, are..desirably.: mounted on individual suppnrting-plates, whiclriaref severally secured to:thtxturntable,` as;.byfwelding, allf as::willfbezdescribed' morein; detailyhereinafter: in: connectionrwith :thiede' scription ofV the. specific-assemblies:

Tillable support mounting,`

As -noted=hereinabove, the gathering mechanisnmmust bermounted bothAfor. reciprocationgaudxtilting; as: well as .being-.rotatable with the rturntable.:

ReferringrnowY to Figs; 1 to 5, and1x7 thetdetailsaof this .mount-ing will be described: 1

A teeter` block .orguide; fulcrum: 70,*tiltablyl'fand rea ciprocablyv mounting. the gatheringsassembly;is;f.-tiltably mounted in guide bearings 60, 60 vineorporatedcin spaced trunnion. supports 50,I 50' (Figs. 3.and 4). Theusupports.are mounted on. the turntable. 30,` inganysuitablev manner. The supports are symmetricaliand comprised1 of the.. following elements: Spaced guide bearingsupports 52, 52'., having hanged' base sections53, 53.', `are secured; inmutually parallel relation to the turntable .30,pbyv ma: chinescrews 54. The supports 52, 52' are-severally'pro` videdzwith top bearing sections 55, 55" having :bearing shoulders'56 at both ends, and a top bearingv surface. 57," terminating in flanged ends 58, overhangingthershoulders 56.2'and forming tongue-receiving grooves 59-.th.erewith:,

The guide bearings 60, 60', are symmetrical andconleprise'lannular body sections 61, 61", integral witlreiia'tl basesections 62, 62'. The base sections have fiatzbear.- ing, surfaces 63, 63', and C-shaped ends- 64, 64- turnedinwardly at 65, 65', and severallyconformed tothe-flanges 53and-tongue-receiving grooves 59,59', of v,theguide bearing supports. The teeter. bearings; or annularbody sectionsl, 61', are provided.with'anti-frictionbearings. 66,. 65', tiltably mounting ,the centrally. aperturecl` `hubs 77, 77' of guide fulcrum 70; Cover'plates:'-67,167' are removably secured. over the outer ends'of the-bearfinga 66, .66' by screws 68, and permit access-fte. thebearings for inspection .and greasing.k

Thetiltable guide fulcrum 70, (Figs. 1,-'4,.-.10,..and-11 as noted, is mounted in theguide bearings,.and,comprises a solid steel body having parallel, liat side bearing:surfaces.l 71, 71', parallel back and front faces72,.73, at right angles to the sides; bottom surfacer 74,topsurface- 75,.with an integral, supeijacent annular boss76, and aligned apertured hubs 77, 77', fortiltably mounting .the fulcrum in the teeter bearings. Spaced ears 78,'.78'y

(Figs. 3 and 1l), forthe tiltlock 80, are formedintegral with the bottom of the fulcrum body, and adjacent the fr ont face .73. The apertured. hubs 77, 77', arev severally` provided with offset ducts 77a and '77b', which. colnf. mnnicate with theram-housing, as will be described more indetail hereinafter.

The tilt jack 80 (Figs. 3 and 11), comprises afcylinder bodyv S1, havingran offset pivotal mounting82,"a-piston` 83S, and-fcommon oil inletand outlet linee-84u '1`hepis`ton 83Tis secured 'at its forward end,` in andvYb'et-weenhthezlugs: 78, of -the teeter block-70,5.by Ymeans-ofaepin `79.' .Uii-

directional-show 1-ooihintor ltleflocks-:chamb er fromesupply lineaifla is,` permitted ilbyi 'za'fcheok valve iinzvalvercontrol 291) sandzreturn of; oil. is-.mader to sump. .liner 285;:

Gathering assembly The ygathering assembly. ofv thezfimproved'rcoaleloading machine .herein comprises a `loading head, incorporating a .rotatabley shovel orscoop-bucket, ,aecasterzwheel. supported-crosshead..mounting .fora the: shovel;- ai:.;powen ram. and associated traveling. or... telescopingamanifold guide vrods fixed: to thel crosshead-` .andfreciprocableetheree with, and a. top rod fon-eiectin'ggrotation .ofthef-advance ingyshovel.;

. The.mounting,; inetherguide :fulcrums .of thepowerfn-ami togetherzwithjts. guide-nods; andthea-'power cylinders as well asthe top rod; .will :nowffbef` considered .withtrespect to the-special 'structuralAf-'featuresf of? thea". fulcrum ape` purtenant.v thereto. The teeter bloc-le. orguide fulcrum 7tiyjFigs. 1,--.,2,;;3,..4,f,10.-andyll,.is provided with avacentral aperture .-911- and: lateral i apertures .191,.1 91" .havirigtatheir centers lying` ini; the. plane. of.I the central. axis .of:.the. alignedlhubsf; 77,' 77 f, andV v at; right.. anglesrthereto. :The: aperturef-QlA-isr formed with threaded sockets 92,193,- at the ends-f thereofgand the.A lateralapertures. 9'1,.,91f,.are severally lprovided. with bronze-'1Y bearings;` 94; 941 Tliel ton-.boss 761-isi centrally aperturedwat; vinrialignment with.' `aperture f90-,5 and .is provided with :a bronze:l bearing! 95;.- The ooss 76 and `bearing 95:21u::transverselyI slotted@ at .the :frontfaceo receivez the., forked'. rack-.1

Referring', more particularly to Fig. 412,3tl1'eqaperture 9.0. andfitsfthreadedsocketsfserve to mount;the;.forward ends oft.th.e,,ram housinggor b0ot.1tl1-,uram cylinderf120, and ram piston rod 128, in the following mannerzff;

Socket 93?; receives. the-v forward fendf- Aof.T bootalhin threaded engagelnentf.; Smiling; Abox, 963-;-isi1threaded-:intoi socket.` 92.' The central portionx'of the .stuflngboxfis threaded .tofreceivez the internally. threaded. forwardend of ram vcylinder `121i. The stuiiing. 4box. is:.provided .fur-g` ther, with a Lslip ring 915i and .athreadedfjournal 97,1in

whichgpiston' ,rod- 12S. -reciproc.ates;v A piston-rod support 981--is5threaded `into aperture 92'in locking.: engagement withfst-u-ng .box- 95, and; vis lpermanently secured .in lock-` ing, positiony by :machine screws. 99.;

Thefpowenram or` piston.- actuat1'ng.1n'ec:h'anisin,- desigr: mated-.generally bythe numeral4 100,.'comprisesnanfouter;` cylindrical housing. or boot, `an inner ramcylinder; and: a piston or ram. The outer cylindrical housing or boot 101, has a lapped outer bearing surface =102,.and a lapped inner surface 10.3 with splines .104 extending therealong. The` cylinder :101 is'screw-threaded at both ends, as indicatedat .105, 106.. Aring 107, having an annular oil; groovey 10S-puits forward face, is tted on andiover the. surface 1(92 of `the cylinder, with its.grooved faceflush' withl thefroot ofthe screw. threads;105'. Th'e ringlo'v isweldedinplace onpthe boot,and serves asa lshouldered bearing orstopth'erefor when itsthreaded Vend section 105lisiscrewed'upnto threadedsocket 93"of the teeter. block or fulcrnrn4 guide 70,' with. the grooved vface off bearing Aring 1137 jammed against the rear face 72 of. thefulcrum guide. Desirably, a .suitablekgasket isLtted. on and over the groovedface of the bearing ringto insure an--oil-tight assembly.

Atits rear end, the boot 101'is providedwitha tubuf lar extensionor .boot headllt), 'which is threaded up on-V the screw threads 166, or preferably welded to the .boot, as-shown-Y atl-'. (Figs. 1, 7, and.-9'),p to.fo`rm anin'tef gral extension thereof. As shown in detail 'in Fig. `9',`-..tl1"e.. sectionll is provided .further with a transverse web 1111,.. having` a central aperture 112,*tapered at 113 toreceive a clamping stud'130. The .end '114 of the .extension110` isy internally threaded' at `115f`to receive` screw-threaded. cap 116 inepressure-tight, hermetica-lly'gsealed';relatio'n,.. wherebyrfto form the closed end of bootllll'.' They charm b'erL formedfin section l 110 by f and between' -foraminous web 111," and"cap-11-`6 fis designated'generally by the numeral 117. The cap 116 is desirably provided with a polygonal boss 118 to permit the use of a suitable wrench in screwing up and unscrewing the cap in its threaded seating and sealing engagement with the rear end section 110 of the power cylinder boot 101. While a boss sealing cap is shown, it will be understood that the outer face vof the cap may be socketed to receive a socket wrench. A plurality ot' pairs of diametrically opposed, concentric, threaded tap holes or sockets 119, are formed in the outer face of cap 116, and serve to receive back bar securing and spacing studs, as will be described more in detail hereinafter.

Fixedly secured in the boot or housing 101 is a ram cylinder 120. This cylinder is threaded at its front end 121, which is screwed up onto stuffing box 96 in teeter block 70 in advance of the boot 101. The rear end, 122, of the ram cylinder is closed by a cylinder head 123, desirably welded in place. The cylinder head is provided with a tapped central aperture which receives one end of a head clamping bolt 130, mounted in boot head 110, as will he described more in detail hereinafter. The cylinder head is provided with a plurality of concentric apertures 124 opening into the space 125 formed between it and the boot head, and serving as oil or hydraulic fluid entrants to the interior of the ram cylinder, behind the ram piston 126. The ram piston is comprised of a pair of leather cup Washers mounted on a steel spacer and secured thereagainst by steel washers. The piston is secured on the threaded reduced end 127, of piston rod 128, by a suitable piston clamping nut 129. The forward end of the piston rod is journaled in a bushing 73', secured in the front face 73, of the teeter block.

It will be noted that the front end of the ram cylinderdenes a piston chamber with the piston 126 and the front piston rod bushing. This chamber is in tluid communication with the in pump connection through duct 77. The forward end of the ram boot defines a second fluid chamber with the exterior of the ram cylinder, which chamber is in fluid communication with the rear end of the piston through splines 104 and cylinder head 123, and with the out pump connection through duct 77. As already noted, ducts 77, 77 are formed in the axis of the teeter block 70, and are severally provided with olset leads 77a, '771), to the uid chambersV formed in the body of the teeter block, as above described.

Side rods and mounting thereof As noted hereinabove, the front end of the ram piston rod 128 is iixedly secured to the front or loader crosshead 220. Telescoping, or collapsible manifolds are integrated with the front crosshcad, the rear support, 180, and the back bar, 150, and are comprised of side rods reciprocably mounted on and over hollow xed pistons serving as oil retrievers. The parallel hollow'side rods 140, 140' are severally secured to the front crosshead 220, and are respectively mounted for reciprocation in the bushed bearings 94, 94' of the teeter block or guide fulcrum 70. The side rods are substantially co-extensive with the ram piston rod 128, and reciprocable therewith. The interiors of these hollow rods are severally designated by the numerals 141, 141'. The rear ends of the rods are iixedly secured to the rear support, 180, as will be described more Vin detail hereinafter, with their threaded exteriors capped and packed to form stuffing boxes 142, 142', which serve as journal bearings for oil retrievers 143, 143. The oil retrievers are hollow tubes threaded at their rear ends, and fitted into apertures 151, 151 at opposite ends of back bar 150. The tubes are shouldered, as shown, and are locked in place in the back bar by retriever clamping nuts 1441, 144. The back bar 150 is provided with a second set of spaced apertures 152, 152', adapted to register with threaded holes 119 in the boot cap, and be secured thereto by means of spacer rods 153,V 153', having threaded spindle ends, one end ofeach rod being threaded into a tapped socket 119 in cap 116 of cylinder 101, and the other end passed through the cooperating aperture 152 or 152', in back bar 150. The shouldered ends of the spindle sections serve asy stops andY provide bearing engagement against the inner face 154 of the back bar, positively securing the latter to the cylinder 101, which, as already noted, is Aitself positively secured in and to the teeter block or guide fulcrum 70. A third spindle 157 lis threaded at both ends, and is tapped into cap 116, while its free end receives back bar clamping nut 158.

The forward ends of the oil retrievers 143, 143', open directly into the interiors of the side rods 140, With this mounting the side rods are reciprocable in the teeter block 70, together with the ram piston rod, while the oil retrievers remain fixed and stationary with the ram housing assembly 100, which, as previously noted, is ixedly secured to the teeter block. The hydraulic controls for the several parts will be described in detail in the specic recital of the control features.

The remaining unit of the hydraulically controlled reciprocable members is a top rod 160 (Figs. 1, 3, 4, 6, 7, 8, 10 and 11), mounted for reciprocation in bronze bearing 95 of the top aperture of the guide fulcrum 70. The top rod includes a tubular body section 161, having a forked steel gear rack 162 welded into the front end thereof. The forks of the gear rack are provided with depending gear teeth 163, operable to effect rotation of the loading bucket, the details of which operation will be discussed in connection with the assembly and operation of the loader head. n

The tube 161 mounts a rst steel slug 164, a compression spring 165, and a second, bronze slug 166. The rear end of the top rod casing is shouldered to receive apertured steel cap 167 in screw-threaded engagement. A plurality of suitably spaced notches, designated generally by the numeral 169, are provided on the bottom surface of` top rod or tube 161, and are adapted to be engaged by solenoid controlled detent 169', which is mounted in the upper portion of teeter block 7i), and rearwardly of the top rodjournal '76. A fixed piston rod 170 comprising a hollow tube is secured in rear support 180, by clamping nut 171, and is journaled in bronze packing box 172, which is formed in the end of tube 161 by the end cap 167, cooperating with the threaded end of the top rod casing, and leather cup washers 173. The piston rod has a central passage 174 discharging through diametral ports 175, 175 into chamber 168 in the rear end of the top rod housing. The piston rod is in uid communication with the interior of telescoping manifold or side rod 140', through pressure line as shown in Figs. l, 4 and 7. The front end 176v of the fixed piston rod is threaded and mounts the piston comprised of leather cups set over steel washers i 177, the assembly being secured in place on the piston by steel nut 178. The rear face of bronze slug 166 is recessed to receive the threaded forward end of the iixed piston.

The rear support (Figs. l, 6 and 9), designated generally by the numeral 189, comprises a unitary casting having a central aperture 131, side apertures 182, 182', in horizontal axial alignment with the first said aperture, and an upper boss 183 mounting the xed piston of the top rod. The central aperture is provided with a bushing 184 for bearing engagement with the lapped surface 192 of the ram boot 101. The lateral apertures mount the side rods 140, 140', of the telescoping manifolds, which, as noted, are provided with suitable journals or stufling boxes 142, 142', to receive the oil retrievers 143, 143', which function as xed pistons for the reciprocable side rods or oil delivery cylinders of the manifolds. As will appear more in detail hereinafter, the side rods and their fixed pistons, together withthe flexible connections to the auxiliary oil pump, form continuously full, expansible reservoirs, providing instantly available oil pressure at Aall times.

agissons Loading.` headi- The' loading jhe'a'd 'of `th`e .novel coal' loader .is' designated generally by the. numeral 2159, and mounts Va. rotatable shovel or scoop buck'et201`." The shovel is of' specialY construction; comprising a. semi-cylindrieal" rear portion and av forwardly'extending scoop portiomof 'curvilinear cross-sect'ion;' witha'toothed bucketlip, The developed surface 'ofthe novel cylindroidal scoop' bucket'is' that of a true 'cylinder,' or' which the seniilcyliridricalzrear' bucket portion is apart.A The bucket 'is centrally dividedlby a recess' in -tliesemicylindricalrear-'portion and a transverse stiffeningavebjoining theiwall of'the bucketto the inneror. bucket face ofthe'recess,` the walls" or" the .recess .being supported 'and "stil'enetl by `an integral" U #shaped bracket, on which the bucket is. rotatably rn'ounted.

Considerirrgthebucket moreindetail; and as shown in the` drawings, the surface" comprises a semi-cylindrical back section" 202 and" a forwardl'yl'extendingv curvilinear scoopsection 203. Th`erea`r"sectionhasaitop edge 202i lying in'a dianretrai plane" of' the* semi-cylinder`,1.whose` axis or longitudinal center is designated by the numeral 29S" (Fig. 4). The' front' edge.' 2%.' of ithe bucket is toothed." Endplates-ZGT 267, aresecuredover.'andon the curvilinearbody section,V being. conformed thereto, and are formed with chordate. topedges ZSgZS'Qseverallyjoining therear'edge Ztfwithtlie frontedge or lip 266. It"'w'ill be'not'ed that the radial distance from the axis 205' to the' .lip 'is approximately equalto 'twice Ythe distance' between'axis' 205andre'ar edge 262i, orto the diameter of'tiie semicylindricalback or bdyfs'ec'tiori ofthe bucket.

The'buck'et mounting ineans"(Eigs'.` l, 4,' l'l` and' 13.), comprises a Ufshaped'bracketli). securedtothewalls of ythe"`couforn'e'd'recess2'1`iiri 'thecentra'l rear 'section of the`bucket'by rivets or 'other securing means; designated generally by the numeral 2121' A web or stifi'ening'plate 209,'pa'ralll to the endplates, is secured to the inside of the bucket and the 'forward surface of the'reces's'.

The bracket 2id, comprises afront wall section.2`12`, of rectilinear shape, with side walls 223', 2'3n. The bracket walisecti'ons are securedito tl'i'e .front and side` walls ofreces's' .by machine screwsZZlL Dalquadrant gears 215, having gear 'teeth 216, are integra-l' with or xedly'secur'edtoth'e back'of front Wall section .22`2' The bracket side walls' andthe quda'ntgears 'are provided with aligned' axial apertures to; receive axis V2.3i?,` which may be iixedly secured in place,.or rotatablytttedthlerein. The axis27 coincides with the Vaxis 2i5"of"thelsemi. cyiindiicalrerbodysectionof tlieibuc'ke't.'V The. bucket' is divided into-two partsv by 'the mounting braclietrecess 211 and the stit'ening web'v Ziiland the rear eds 21M is comprised. of aligned and concentric portionslz, 2041i, of the concentric bucketv portions 292th 202B; The forked rack 162 is' journaled'in theguide or slide` formed. by bracket section Zand'capvpiate 218,1with the t. upper surface Voflthe rack havingre'ciprocating, bearing engagement'-tvitii' the under surface of the. cap plate, and.l the rack gear Vteeth 153being..in mesh with. the gear. teethA 216 of quadrantgear's-HS; whereby reciprocation of the gear rack will eect rotation ofthe scoop bucket'about' its axis.-

The bracket-supported scoop or .bucket 2't1`is 'mounted for rotation-on crosshcad 22S', which', as noted, Ais xedl'y secured 'to ram piston-rod 12B audits cooperating.,side.rods` 1401 Mtl. The crosshead is desirably a'unitary' casting having a front top'section anda depending rear 'section oii'set fromthe' top"section:` TheV front's'ection 221" is"V to provide 'clearancefor-quad--- grooved, as shown at* 222 rant gears 215; A lockingor cap` plate l2-l;8"alt uts` the bracket elements 212, 23, 213', with its topY surface'us'h with theirupper surfaces. Thispl'ate'is securedJ in' place by theusual machine screws 214.'

The loading head 220iis' mounted generally forflorizoni tal reciprocation byfand with the actuators' 128'and"1"60;- and to` prevent the empty orloaded scoopbucletfrom 'erally by." the= numerallf239.V

imposing unsupportedzloadsson itsrssupporting mefnbeizn` mounted underneath .therear .section 223 of crossheadf220g and intheicentral.vertical'axis about which the bucketv rotates:

The support'.'wheelnrounting comprises an inverted bracket 225,. havinga top member;226 and depending legs 22.7. 'mounting-axis-228uon which z Wheel 224 is secured. The .member 2261s .swiveled on the outer surface.v of the crosshead by axis 229. With thismounting, thev weighto. the bucket ZGIis supported. by the wheel 224 in all h'ori-44 zontally extended positions of th'e'loadingvhead.`

Front or pull jacks A specialfeatureof the inventionherein isztheuin.-Y corporation of selfepropulsion means .inthe coal-loader, whereby the machine'. can be self-propelled to any. desired location, and solely by means of its own power plant;y To.'` secure this desirableeifect, hydraulically actuated front or pull.; jacks-.alsol known as' grab"A or; walking jacks-are mounted in the crosshead 22u in the following manner:

A pairA 0f: piston chambers236, 231 are formed in the central vertical axis lof cross head 220, between .the bucket aXis21-7 and the clampingplate 129fwhich locks the'front end .of rampistonv rod .128 to' the cross head. These chambers are severally offset at'. a rearward angle, as shown-,i-arndare-interconnected"by aduct or opening 232, which is in fluid communication withside rod y140.' through ducti 233, as Willbede'scribedmore in detail hereinafter. Thebottom jack-comprisesrthe lower piston chamber 230,` mounting 1a.piston:235fhaving a-pointed tip236, a rear ilange 237,. and.acentral1recess 238vextending from the rearffendiv of thepistonfto the tip section thereof. The piston isi journaled! in ta4 suitable bushing, designated Vgen- T heftop jack, comprises a telescoping pi'stonfZY-tglmountedfor reciprocation inupper piston ch-amberrZSl. This device includes an outer sleeve piston 241 havingabottomange242 in bearing engagementswith the wall offchamber 231, the upper end of which is closed by ybushingf243 inwhich piston 241 is jourlnaled. A second,` hollow piston 244, has aA central recessl 245,1- apointedtip 246,1.and a'bottom flange. 247 'in bearingengagernentf with the inneriwallof sleeve piston 241. Piston 244isjournaledlin bushing 24S-iat the inside ofthe.upperendo'sleeve piston 241. The pistons are normally"tbiased'inter-retracted 'position (see Fig.: ll) b'y tension-spring. 250,"- whichfis ttedfin` the kpiston recesses 238'! and 245,. extending through central' opening' 232. Spring=25ttisvsecuredto-tlie opposed'pistons by transverse pins251, 252`in`pistons-23S, 240. The pin sockets are sealed fromithe piston centersby.sunken'machine'screwg designated generallyby the numeral 253;

Itwillbei noted tth'at lwhen hydraulic actuatingtluidvv is -forced:throughduct 233'intothe inter-'chamber'spaoe 232, the-lower,v and.' upper pistons 235, 240 are driven outwardly,*.againstfthe-bias-o1tension spring 250. Because of'ith'e supporting.'.wheel""224, insuring `the normal horizontallposit'ioning.' of 'tl-Ie" ram assembly 100,' lower grab jacltlpiston 23S-has; a' limited, hxedv trajectory, to theA oor oftheworking,` while, owing'torvarying roof heights of` different workings, the*y telescoping upper grab jack can beextended to any. required lheight, and a uniform hydraulic pressure is 'applied to' both jacks;

The :specific functioningfof-tthe pull jacks as elements of'the.self-propulsion; system of the coal loader will be discussedmorefully in connection with thedetail'cdde script'ioniofilthe:hydraulic `actuating system and its vinterlocking solenoid valve' controls. At this point, it is to be notedth'efront jacks-are self-anchoring, dueto their rearwardtilt/ severally imparted by thel respective piston'- chambers.

Hydraulic actuating mechanism Anzimportant.' feature` of the invention herein.. is the improved actuatingij system. which insures positive,- li've 15' hydraulic control ofthe` bucketoperatin'g' mechanism by providing a continuously pressurized hydraulic actuating pump system therefor, so that the main hydraulic unit is not subjected to varying operative loads, but is concen trated on its main job of powering the ram piston.

It will be appreciated that the power requirements of the loading head reciprocating system are of an entirely different order from the power requirements of the oil lock for the top rod in its bucket-rotating, locked position, and the power required to actuate the hold jack and the front, grab, or walking jacks. The invention herein comprehends the utilization of a motondriven, dual unit, hydraulic power system, of differential power capacity and pressure, whereby greater flexibility of control is secured, without uneconomical spread in the operative range of a single power plant. Additionally, by means of the improvements herein, the operative characteristics of the basic operating units of my coal loader are greatly improved.

Referring to the drawings, and particularly to Figs. 1 and 2, the details of the dual power plant will be considered.

The power plant for energizing the hydraulic actuating mechanism comprises a pump unit 260, driven by motor 271; an electrical control cabinet 279 mounting the push button controls; and a valve enclosure 280, mounting the solenoid valves 310, 315, and 320.

y The pump unit comprises an enclosed casing 261, divided by an inner wall member 262 into a main pump chamber 263, and a corner reservoir 264, of generally triangular' cross-section, and in fluid communication with the main pump chamber. A pair of outlet ports 265, 266, and a pair of inlet ports 267, 268, are formed in one wall of the casing, as shown. The pump 270, is powered by motor 271 through shaft 272, the motor being mounted outside the pump casing 261. Pump 270 is a dual unit having a high pressure and a low pressure end, with inlet connections 273, 274, respectively opening into the pump chamber and severally fitted with strainers, as shown. The high pressure end of the pump discharges through line 275 and relief valve 277 to outlet 265. The low pressure end of the pump discharges through line 276 and relief valve 278 to outlet 266. The dual pump unit 270 and its inlet and outlet connections are submerged in and by the hydraulic fluid in the pump chamber 263.

The valves are mounted in a valve enclosure 280, and the electrical controls in a cabinet 279, appropriate connections being provided to the pump elements and the loader. The valves and their connections are as follows:

.Valve 281 is a double solenoid, spring centered valve controlling the in" and out motion of the ram piston 128. It is provided with inlet and outlet ports 282, 283, severally connected to high pressure pump outlet 265 and reservoir inlet 267, through lines, 284, 285, respectively. A pressure relief valve 286 is mounted across lines 284, 285. 1 Valve 281 is provided further with outlet ports 287, 288, severally connected through flexible lines 77e and 77d to the ram out and ram in connections 77 and 77 in the teeter block axis. When the control button for the out motion of the ram piston is pressed, the flow of hydraulic fluid is from port 282 to port 287, thence through line 77C, duct 77', and splines 104, to the back of the piston 126, applying pressure to the same. Simultaneously, port 288-which is on the free side of the piston-f-is connected through exhaust port 283 to the pump tank return 285, thus relieving back pressure on the piston. When the in button is depressed the procedure is reversed. The in and out solenoids; are mechanically interlocked, so that both of ports 287, 288, cannot receive pressure simultaneously. With the pump running, and neither "in" nor out motion is desired, the valve springs back to neutral, diverting the ow of hydraulic fluid from inlet port 282 to return port 283, and trapping the fluid on both sides of the ram piston, so that the ram piston rod-and attached loader head-can neither move in nor out, and the loader head is locked in place.

The tilt lock control valve 290 has an inlet port 291, connected through check valve 292 to high pressure fluid line 284. The valve is provided further with an outlet port 293 in huid communication with tilt lock feed line 84, and a return port 294, connected through line 295 to the pump return line 285. This valve is a 3way single solenoid spring offset valve, and controls the tilt lock which holds the bucket assembly in a tilted position after the bucket has been loaded, retracted, and is ready for the outward stroke to dump. The supply of hydraulic fluid is from high pressure feed line 284 to inlet port 291, and, when the valve is in neutral, to outlet port 293. With dual pump 270 operating, there is a supply of oil available to flood the tilt lock as the bucket assembly tilts upwardly, when retracted. The check valve 292 traps the oil that is drawn into the tilt lock 80. When the bucket is to be dropped to a horizontal position, the tilt unlock button is actuated, energizing the solenoid that moves the valve, so that the trapped oil returns to the pump tank through ports 293, 294, and return lines 295, 285.

The low pressure side of pump 270 supplies hydraulic fluid for the actuation of the center jack, front jacks, top rod fluid lock, and the two-way turn motor. Valve unit 310 controls the hold jack and pull jacks. This valve is a 4-way double solenoid spring centered valve having the operative, solenoids mechanically interlocked, so that pressure cannot be simultaneously applied to both sides. Low pressure feed line 300 connects pump outlet 266 to valve inlet port 311 through reducing valve 301. Outlet port 312 is connected to the front jacks through line 143a with oil retriever 143; outlet port 313 is connected through line 20a with the center or holding jack 20; and discharge port 314 is connected to sump A264 through return line 306 and port 268.

When the center or hold jack 20 is to be actuated, the center lack control button is pressed and hydraulic fluid ilows from port 311 to port313, and thence to the jack. Simultaneously, port 312 is interconnected with exhaust port 314 and return line 306, discharging the hydraulic fluid from the front jacks which is forced through oil retriever 143 by the bias of tension spring 250 acting on the jack pistons. When the center jack is to be collapsed the solenoid is deenergized, and ports 311, 312 are connected with discharge port 314, and thence to the tank 264.

` When the front or pull jacks are to be actuated, the front jack control button is pressed, energizing the solenoid, whereby ports 311 and 312 are interconnected and hydraulic fluid is driven through side rod into the front jack cylinders, and the jacks are extended and an chor themselves in the oor and roof of the working. With the front jacks extended and anchored, and the hold jack automatically retracted, the loader head is in its extended position. Ram control valve 281 is then actuated to the ram in position, whereby hydraulic fluid is forced between the front face of the ram pistou and the associated teeter block chamber, forcing the teeter block-and the turntable and skid baseforwardly to approximate the loader head in its anchored position. As the loading machine moves forward under its own power the retriever rods are telescoped in the side rods, building up a back pressure in the latter. This pressure is relieved by pressure relief valve 278 in pump line 276.

With the machine in its new, advanced position, the hold jack is actuated, thereby automatically releasing the front jacks from their grab or hold position, and freeing the loader assembly for normal reciprocation in load'mg and unloading.

Valve 315 is a 3-way double spring centered solenoid valve which controls the ow of hydraulic uid to the fluid lock in the rear of the top rod 160. After the bucket has been oscillated and loaded, this lock maintains it in its up position. The valve includes inlet port'316, outlet port 317 connected to the lxed piston 170 of top rod 160 "by, line 170', side` rod 140', retriever 143?, linev 170:1; and'disc'harge port 318 connected to the sump 264 through return line 307. To maintain the up position of thebucket the control button is pushed to'establish fluid connection between ports 316, 317 and line'170a'to the top rod. Line 170' connects piston 170 to side rod 140 and its oil retriever 143', whereby they form an expanding surge chamber or reservoir. As the bucket is retracted a high pressure may be built up in the' side rod 140', which, as noted, is a telescopic manifold; Such a pressure is overcome by reverse llow through line170iz and feed line 302-to the return vline 306, the return being eiected through pressure relief valve309, which bridges the hydraulic fluid supply and return lines 302, 306. Check valve 303 is inserted in the line between the pressure relief valve 309 and the pump-outlet 266. This checkvalvev guards against the building up of a pressure in excess' of the predetermined or set pump pressure from entering valve 310 controlling the center and'front jacks.

Valve 320 controls the hydraulic turn motor 40. This valve is a 4way double solenoid spring centered solenoid valve. The valve incorporates an entry port 321, a pair of outlets 322, 323, anda discharge port 324 discharging to the sump through lines 308 and 306. Ports 322, 323, are -respectively connected to the turn motor through lines 325,326. These lines'may also be designated as right turn line and left turn line, respectively. When the platform`30, with-its contained loader equipment, is to be rotated to the right, the right turn control button is pressed. This energizes a solenoidl to move the valve tointerconnect ports 321 and 322, to thereby establish afluidfpressureconnection to the right turn side of the fluid motor through line 325. Simultaneously, ports 323 and-'324 areinterconnected, establishing free connection of the-left turn sideto the sump andrelieving the back pressure in line 326.I To rotate the turn motorto the left, the left turn button is pressed, ,energizing the left turn solenoid whereby ports 321 and 323 are interconnected on the inlet side and ports 322 and 324 are interconnected on thedischarge side, reversing the procedure. Both the.l solenoids are mechanically interlocked4 so that both sets of' ports cannot be opened simultaneously. Hydraulic fluid, under pressure is supplied to inlet port 3,241,l through sequence valve .305 in branch feed line 3042 When valve 31S is set at neutral, the pressure lluid is lay-passed or diverted to line 304 through sequence valve 305, whereby the top rod is locked and the bucket irnmobilized during the rotation of the machine in any drection.

The novel coal loader is adapted for both direct and remote control. With direct control, the operator is seated at the rear end of the machine and the push button switch controls aresecured on the hydraulic unit, the con-` trol box being positionedon the opposite side -ofthe plat? form. With remote control, the controls are mounted on a single instrument board, which is set up in the mine chamber at a'point remote from the machine, and'is connected to the machine by a suitable ilexible power cable. As will be seen in Fig. 3, a main power cable 190 is introduced into the skid base of the machine through aligned entrants 8 and 5, then up through entrant 18 in the hollow bottom portion 11 of vertical shaft 10, and out through top apertures 19 to the slip rings, designated generally by the numeral 191, which are mounted on insulating cylinder 192, secured over shaft 10. Brushes 193 are mounted onstandards secured to the turntable 30, for rotation therewith, and are suitably connected to the motor 271.

acrerized by an extraordinary simplicity of construction', with a resulting.' facility of operation, such that maximum 14,? oiitput-y is seo'uredf-with aimi-nimumfot ener-gy'input and operative control..

When' the 'coal'z loader-"is ttoA bei'op'erated,a.it` is-brought into position at the faeevoffthechosen working; which has 'been' previously fpro'vided' with` an endless belt 'conveyor or other 'suitable'means-for removingthe coal to fthe mainarteries off theworkings'. Thefcoal loaderbeingset in itsoriginal, ydesiredg-,op'erating location, the'power lines, eitherelcctric or hydraulic,' are'coupl'edtofthe power supply, andthe operatorf'take's overfatfthescontrols.- As explained hereinabove;j the operatorfand v'the vcontrolsI may be on' thecoa'l loader-fitselfgor.stationedxata distance'from thef machine, and "connected the-reto r by vsuitable control leads;

The hold-jack control .is'srsteenergizedj opening up, the valve, controllingithe"adniissionfoffpressure iluid to the holdijackpiston cylinder; whereby the ja'cleis vmoved into roof-engaging 'Contact' with? the.v rooffofi the working; vandv the jack* cylinder,fwitli fits ysupportingturntable andl skid base, isforced downwardly; whereby the skid base is firmly seatedY on the"l floor*ofPthefworkit-lg,I withthe machine pivotedi about'- the. 'hold-jackff as? an'axis of' rotation. A check-valve 'in the? presslneffluidfeedA YlineV locks the kholdjackin place; When Y'theirhold-jack#is'energized, the pressure fluid feedlineto theigrabor'traveling jacks, mounted' inthe loader.'headfsupportyisf'coupled 'to the' 'return line tothe pump sump, and'th'e Sgr'abLjack pistons' are retracted byJtheir' retractilefbisin'gspring; with'a` concomitant forcingsofanyfpressurebuidin the` grab-jack cylinders Vback into thereturnline.y

Usually, .ther coal loading fhead'` is .carried at itsv fully retractedipositon; .whenfthef'rnachineis fnotractually engaged in coal loading;y Inzthisfposition'g"the sidelrodsand-rarn supportingithe Vloadi-ngrhead` a'reretra'cted, and f-th'e bucket orfscoop Ais-'supportedfon? and-'fby' a swivel' wheel having bearing-engagement. with fthe floor ofthe working; The serrated' lip' of'V therbcket 'is carried iatrip ofthe iioor vof the'- working. TheiramA out control is now'actuated', andi pressurel fluid; frorn-thehigh' pressure side of the' power'unit, is introducedvbehind'ftheram piston, forcing the ram andattach'edloading head forward until the lip Vof, thebucketfenga'ge's' thefbottorn'fof the coal pilevat theface'of theu'zorking;v Intliisforward' travel, the side rods are carried forward, as is the top rod. The topfrod is Yprovided with suitable detents which are engaged by a solenoid-controlled stop-v memberwhen the lip of the shovel has contacted-thelbottoin of the face of the coal pile which is tobeloaded. Astherarn continues its forward travel, theflip'of the'bucket is forced into-the coal pile, and scoops up a bucketA load of coal. The scooping-up actionV ofthe bucket is effected bythe en'- gagement of 'the quadrant gears' of the loading head with the'` now stationary racks carriedat thefront-of thetop rod, whereby `the forward travel of: the loading head' carriesthe quadrant gears forwardly, and, being .restrained'by the" stationary racks, they are rotated', vcausinglthe"arcuate or scoop'ing. movement of'the'bucketaboutits axis.v The scooping movement of thebucketis accentuated bythe continuing forward travel of the loaderhead, soI that a fifty (50) percent increase in loading capacity iseffected. When the top rod is being carried forward by the loader head and the traveling support, pressurelluid is aspirated into the top rod locking cylinder through its xed piston rod, which isfixedly secured `to and carried by the travelingesupport. The pressure fluid line supplying the top rod locking cylinder is provided with a check valve, whereby uid in the cylinder is immobilized, effectively locking the top rod against forward motion, after it has been initially stopped by the detents. With the scoop'in its turnedlup, fully loaded position, and locked against rotation about its own axis by the interengagement of the quadrant gears with the racks-on the forward end'of the now locked top rod, theram-in control is actuated.

Pressure fluid is-forced in to the ram cylinder forcingY the" ram' back with' the 'loaderheadfand its' contained! load-.

aisance The retraction of the ram forces pressure fluid from its out side back into the pump sump, and the excess weight of the teeter-block-mounted ram cylinder housing, or boot, the traveling support, and the top rod, will overbalance the loaded scoop, raising it off of the ground. The raised, loaded scoop is rotated to a suitable discharge or unloading position by actuating the turn motor in the desired direction. When the unloading point is reached, the top rod locking cylinder feed line is coupled to the sump return line, whereby the unbalanced load of coal in the loading bucket causes the bucket to rotate about its axis, and discharge the coal. The rotation of the bucket to its coal-discharging position is accompanied by the advance of the top rod in response to the pull of its forward racks by the rotating quadrant gears of the loader head. The advance or forward movement of the top rod is accompanied by the forcing out of pressure uid from the locking cylinder back into the pump sump. The turn motor is now actuated to return the loading head to its coal loading position, the ram out control is actuated, and the loading cycle is repeated as often as desired.

When a given Working is exhausted, the machine is moved to a new loading position in the following manner:

The loading head is advanced to its forward, loading position, and the grab-jack control actuated. Pressure' fluid is forced into the grab-jack cylinder, forcing the upper and lower pistons, against the bias of the retracting spring, into gripping engagement with the roof and door of the working, respectively. When the grab jack is actuated, the hold jack is simultaneously connected to the sump line, the hold-jack piston sinks under its own weight, because of the release of pressure, and the pressure fluid in the hold jack is forced out into the sump line.

With the grab jacks anchored in place, the ram in control is actuated. The ram being anchored in its forward, extended position, by the grab jacks, the pressure fluid will exert pressure on the stuiiing box in which the ram is journaled, and the teeter block will be forced forward, carrying the turntable and its skid support with it. Upon completion of the forward travel of the skid support to its new location, the hold-jack control is actuated, automatically anchoring the hold jack and skid in place, and simultaneously releasing the grab jacks from their ram-anchoring position.

The coal loading and unloading operations are then continued in the manner described above. Turning now to Figs. 14, l5, there is shown a modified hold-jack assembly which is particularly adapted for use with low pressure hydraulic actuating fluid. The assembly, designated generally by the numeral 350, comprises a pair of hydraulic jacks 351, 352, iixedly mounted, in opposed relation, on annular casting 37 which, as previously noted, serves as theY hub for turn-table 3). The central post 10 is specially iitted with a hollow piston 21a which reciprocates in the chamber 17 formed in member 10. The top of the piston 21a secured in a yoke 353 and moves therewith. Member 353 is provided with sockets 354, 355, at opposite ends thereof, and with a circular, shouldered aperture 356 adapted to receive a conformed plug member 357 having socketed bearing engagement with the bearing plate 29. A tension spring 358 is secured between the member 357 and a shackle 359 made fast to the bottom of piston chamber 17.

The hydraulic jacks 351, 352 are of identical construction, and comprise base elements 360 xedly secured to or integral with hub 37 of the turntable. The members 360 are circular and are channeled as indicated at 361 to receive the cylindrical casings 362 of the jacks. Cap bases 363 are mounted on the casings 362 and receive pistons 364. These pistons are provided with stub shafts 365 on thc top thereof, which shafts are received in the sockets 354, 355 of the yoke member 353. Entrants 366, connected to a manifold, not shown, are provided at the bottom of casings 362 to permit hydraulic fluid, supplied thereto from supply line 20a, to be forced into the piston chambers against the bias of Spring 358.

The improved hold jack construction is characterized by positive function with the expenditure of minimum energy in pressure uid. When pressure iuid is admitted to line 29a, the pistons 364 are forced upwardly in their piston cylinders or casings, and carry the yoke or plate 353 therewith, against the bias of tension spring 35S mounted in the central piston channel 17. With the bearing plate or head 29 of the jack in clamping bearing engagement with the roof of a Working, the coal loader is secured about member 29 and shaft 10 as a fixed pivot. When the grab-jack assembly is actuated, the entrant 20a is automatically connected to the sump of the hydraulic power unit, and the tension spring 358 acts on plate 353, through member 357, to retract the plate and the attached pistons 364, whereby the hydraulic duid in the piston cylinders is forced out through inlets 366 to the supply header and thence through line 29a to the sump.

It will now be appreciated that there has been provided a novel ycoal loading machine of simple design, and greatly increased loading capacity, which can be jacked into any selected-working position, under its own power, and which is actuated by hydraulic pressure iiuid delivered to the operating mechanisms through interlocking controls, the iiuid being pressurized in a unitary pump assembly. It will also be appreciated that the novel coal loader herein is of compact, yet rugged construction, and, while designed primarily for operation by hydraulic pressure iiuid, can be operated by suitable electrical or mechanical actuating equipment.

While I have shown and described the preferred embodiment of my invention, I wish it to be understood that I do not confine myself to the precise details of construction heren set forth by way of illustration, as it is apparent that many changes and variations may be made theerin, by those skilled in the art, without departing from the spirit of the invention or exceeding the scope of the appended claims.

What is claimed is:

l. In a coal loading machine of the character described, telescoping manifolds comprising reciprocable tubular side rods iixedly secured at both ends in a swivel wheel-V supported loader head and a back support, said loader head, back support and side rods forming a structural entity; a combination tilting and rotating support mechanism comprising a teeter block including means for receiving the said side rods in sliding bearing engagement; a pair of tubular pistonstelescopically litted in said rods and in fluid communication therewith, hermetic bushings in the rear support member forming pressure tight fluid seals for said pistons, a back bar xedly mounting the rear ends of said pistons; hydraulic fluid supply means to the rear ends of said pistons, and means to control the fluid pressure therein, whereby the said rods and the pistons of the telescopic manifolds are kept iilled with hy- 'draulic fluid.

2. In a coal loading machine of the character described, telescoping -manifolds comprising reciprocable tubular side rods iixedly secured at both ends in front and rear support members, said support members and side rods forming a structural entity; a combination tilting and rotating support mechanism including means for receiv'- ing the said side rods in sliding bearing engagement;'a pair of tubular pistons telescopically fitted in said side rods and in fluid communication therewith; hermetic bushings in the rear support member forming pressure tight uid seals for said pistons; a back bar iixedly mounting the rear ends of said pistons, whereby the side rods are reciprocable thereon and thereover; and valved hydraulic iiuid supply means connected to the said rear ends of said pistons.

3. In a -coal loading machine of the character described, telescoping manifolds comprising reciprocable tubular side rods iixedly secured at both ends in front and rear rrr:

rasgos support members, said support members and side rods forming a structural entity; a lxedly mounted combination tilting and rotating support mechanism including means for receiving the said side rods in sliding bearing engagement; the front support comprising a loader crosshead mounting a grab-jack assembly and the rear support member comprising a traveling top rod support; a pair of tubular pistons telescopically tted in said side rods and in fluid communication therewith; hermetic bushings in the rear support member forming pressure tight fluid seals for said pistons; valved hydraulic fluid conduit means connecting the rear ends of said side rods whereby huid connection is established in and between the said side rods, the top rod and the grab-jack assembly; a back bar xedly mounting the rear ends of said pistons, and spacedly secured to the combination tilting and support mechanism and hydraulic tluid supply means connected to the said rear ends of said pistons.

4. In a coal loading machine of the character described, telescoping manifolds comprising reciprocable tubular side rods xedly secured at both ends in a swivel wheelsupported loader head and a back support, said loader head, back support and side rods forming a structural entity; a combination tilting and rotating support mechanisrn comprising a teeter block including means for receiving the said side rods in sliding bearing engagement; a pair of tubular pistons telescopically litted in said side rods and in huid communication therewith, hermetic bushings in the rear support member forming pressure tight fluid seals for said pistons, a back bar fxedly mounting the rear ends of said pistons; hydraulic fluid supply means to the rear ends of said pistons; a ram piston housing xedly secured in and between said teeter block and said back bar; a ram piston reciprocably mounted in said housing and fxedly secured to and supported by the loader head; a percussive top rod journaled in said teeter block and normally movable with the loader head; and hydraulic check means for arresting forward movement of the top rod, whereby on continuing forward movement of the loader head, a percussive impact is imparted thereto by the top rod.

5. In a coal loading machine of the character described, telescoping manifolds comprising a pair of tubular side rods xedly secured at both ends in a swivel wheelsupported loader head and a back support; a combination tilting and rotating support mechanism comprising a teeter block including means for receiving the said side rods in sliding bearing engagement; a grab jack header in the loader head in uid communication with one of the side rods; a pair of tubular fluid retrievers telescopically tted in said tubular side rods in uid communication therewith; hermetic bushings in the back support forming pressure tight fluid seals for said side rods, said loader head, back support and side rods forming a structural entity; a back bar fixedly mounting the rear ends of said retrievers; a power ram housing and a ram cylinder iixedly mounted in and between said teeter block and said back bar; a ram piston rod in said ram cylinder and having sliding bearing engagement in said teeter block, said power piston rod xed to said loader head and reciprocable therewith; a first hydraulic supply means operatively connected to said power cylinder, whereby to reciprocate the ram piston rod, and a second hydraulic fluid supply means connected to the rear ends of said retrievers and severally establishing fluid communication therewith.

6. In a loader, a crosshead, means for supporting the crosshead, a ram piston rod for projecting the crosshead and retracting the same; a quadrant gear; an axis integral with the gear and journaled in the crosshead; a loading scoop pivoting on the axis and having a reentrant rear portion defining lateral semi-cylinders whose axes coincide with the axis, said semi-cylinders lying on either side of the reentrant portion; a rack cooperating with the gear; a percussive top rod connected to the rack, said rod being normally movable with the crosshead. and hydraulic con- 13 trol -means for selectively limiting the travel of the top rod, whereby on continued movement of the crosshead, apercussive impact is imparted thereto by the top rod.

7. In a loader, a crosshead, swivel wheel means for supporting the crosshead, a ram piston rod for projecting the crosshead forward and retracting the same; a quadrant gear; a shaft integral with the gear and journaled in the crosshead; a loading bucket pivoting on the shaft and having a reentrant rear portion defining semi-cylinders' whose axes coincide with the axis of the shaft, said semi-cylinders lying on either side of the reentrant portion; a forked rack in mesh with the gear; a percussive top rod connected to the rack, said rod being normally movable with the crosshead, and hydraulic lock means for securing the top rod against forward movement with respect to the ram piston rod, whereby on continued movement of the crosshead, a percussive impact is imparted thereto by the top rod.

` 8. A loader shovel having a generally cylindrical rear portion, a forwardly extending scoop portion terminating in a lip and conformed end walls, said lip extending substantially one cylinder diameter radially out from the axis of the cylinder, a shaft pivotally supporting the loader shovel in the central axis of the cylinder, a segment gear on said shaft, a re-entrant rear portion fixedly mounting said shaft, a cross-head supporting means in said reentrant portion and rotatably mounting said shaft and gear, a rack operatively engaged with said gear, a percussive top rod secured to said rack, means for moving the bucket forwardly and rotating it about its axis during such forward movement, the said shovel being axially movable in a forward direction with the lip initially percussively engaging' and then continuously engaging the material `to be loaded during the co-urse of the forward travel while the shovel is rotated on its axis, whereby to bring the lip horizontally forward a determined distance and thence from a depending position, substantially through to its top loaded position, the contour of the loader being such that the material picked up is continuously disposed in the vertical axis of the loader.

9. A shovel particularly adapted for use with coal loading machines, comprising a bucket having a semi-cylindrical body section with a forwardly extending scoop section terminating in a lip, and conformed end plates, a shaft coincident with the axis of the semi-cylindrical body,

a reentrant rear portion xedly mounting said shaft, a

segment gear on the said shaft, a swivel wheel-'mounted crosshead supporting means in said reentrant portion and rotatably mounting said shaft and gear, a rack operatively engaged with said gear, a rack restraining plate secured to said crosshead, said crosshead and rack being movable to effect initial percussion engagement and conjoint forward movement of the rack and the shovel, and rotative movement of the bucket from unloaded to loaded position.

l0. A-self-propelling coal loader, including a loading head mounting a rotatable bucket; a reentrant rear portion in the bucket; a shaft securedv transversely of said reentrant portion and mounting spaced quadrant gear segments, a swivel wheel-supported crosshead mounting the shaft; a ram piston rod and telescopic manifolds incorporating lateral side rods secured to the crosshead; a forked rack adapted for engagement with the gear segments; a percussive top rod secured to said rack; means for moving the bucket forwardly and rotating it about its axis during lsaid forward movement, whereby to engage with and load coal; self-propelling means for the coal loader comprising self-anchoring, hydraulically operated, opposed grab jacks mounted on the loading head; a holding jack mounted rearwardly of the loading head; and interlocking hydraulic control means for selectively actuating the jacks.

11. A coal loading machine of the character described, comprising a base; a turntable mounted on said base; a holding jack mounted in the axis of the turntable; a tiltable coal gathering assembly mounted on the turntable at one side of the axis and including a gathering head 19 comprising a bucket; means for supporting the bucket and means forrotatingvthe bucket, said bucket supporting means comprising a swivel wheelisupported crosshead; a ram piston rod and telescopic manifolds including tubular side rods secured to the crosshead; a tiltable fulcrum guide mounting the said ram piston rod and side rods in slidingbearing engagement; a ram cylinder and a housing therefor xedlysecured to the fulcrum guide and housing the said ram pistomuid retrievers telescoped in said side rods and severally secured at one end to a back bar; means forV xedly securing the ram cylinder and its housing to the back bar; a back support reciprocably mounted on the ram cylinder housing, the rear ends of the said side rods being secured to said back support and receiving the fluid retrievers in sliding bearing engagement, the side rods, crosshead, ram piston rod, and back support forming a reciprocating unit; arxed hollow piston secured to said back support, a top rod. cylinder disposed about the said xed piston and reciprocably mounted in the guide fulcrum; a quadrant gear-actuating rack secured in the forward end of said vtop rod cylinder, and engageable with said bucket rotating means; a separate hydraulic actuator 'for the ram cylinder and a separate hydraulic locking means forV the reciprocable top rod cylinder; and percussion means comprising spring biased inertia members in the top rod.

12. In a mining loader, a ram piston rod and dual tubular side rods; a crosshead carried by the said piston rod and side rods; a quadrant gear rotatably supported in the crosshead, a scoop shovel rigid with the gear; a cylndricaltop rod movable with the ram piston rod and side rods, said top rod incorporating spring-biased percussion hammer means comprising inertia members; a

guide for the top yrod comprising a back support xedly mounting the side rods and movable therewith; a rack at the forward end of the top rod in mesh with the quadrant gear; hydraulic fluid control means for limiting movement of the top rod; and a tilt lock for holding the shovel in tilted position and operable by retractive movement of the crosshead to its rearmost position.

13. A self-propelling coal loader, including a swivel wheel-supported loading head mounting a rotatable bucket; a reentrant rear portion in the bucket; a shaft secured ltransversely of said reentrant portion and mounting spaced quadrant gear segments, a crosshead mounting the shaft; a ram piston rod and lateral side rods secured to the crosshead; a forked rack adapted for engagement with the gear segments; a percussive top'rod secured to said rack;

means fory movingthe bucket forwardly and rotating it about its axisduring said forward movement, whereby to engage with and load coal; self-propelling means for thefcoal loader comprising self-anchoring, hydraulically 20 operated, Aopposed grab jacksmounted on the loading head; a duplexholding jack mounted,rearwardly of the loading head; and interlocking hydrauliccontrol means for selectively actuatingthe jacks;

14. A self-propellingcoal loader, including a loading head mounting a rotatable bucket; a reentrant rear portion in the bucket; a shaft secured transversely of said reentrant portion and mounting spaced quadrant gear segments, a swivel wheel-mounted crosshead mounting the shaft; a ram piston rod and lateral side rods of telescopic manifolds secured to the crosshead; a forked rack adapted for engagement with the gear segments; a percussive top rod secured to said rack; means for moving the bucket forwardly and rotating it about its axis during said forward movement, whereby to engage with and load coal', self-propelling means for the coal Vloader' comprising selfanchoring, hydraulically operated, opposed grab jacks mounted on the loading head and in iiuid communication with oneV of said manifolds; a duplex holding jack mount- Y ed rearwardly of the loading head, said duplex holding jack comprising a pair of hydraulic cylinders in uid communication with each other, a bearing member secured to and spanning the pistons in said cylinders, said bearing member being normally spring biased into non-operating position; and interlocking hydraulic control means for selectively actuating the jacks.

15. Coal Vloader according to claim 14, characterized by a tension spring in the hold jack, secured to and between the bearing member and the hold jack support, and normally biasing the bearing member in retracted position.

References Cited in the le of this patent UNITED STATES PATENTS 105,883 Bailey Aug. 2, 1870 308,118 ,Whitcomb Nov. 18, 1884 530,210 `Th`ew Dec. 4, 1894 1,359,841 `Russell Nov. 23, 1920 1,861,194 Sloane May 31, 1932 1,704,866 Morgan Mar. 12, 1929 2,302,953 Pocock Nov.v 24, 1942 2,389,921 Mavor Nov. 27, 1945 .2,420,755 Mavor May 20, 1947 2,422,490 Le Tourneau June 17, 1947 2,441,581 'McDade May 18, 1948 2,483,650 Lee Oct. 4, 1949 2,489,898 Kluckhohn Nov. 29, 1949 2,499,620 'Alderman Mar. 7, 1950 '2,530,714 McDougallv Nov. 21, 1950 2,558,165 Anderson June 26, 1951 2,567,390 Mead Sept. 11, 1951 

